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Cobalt analogues of Roussin's red salt esters: a density functional study
Menyhárt B Sárosi1, R Bruce King
1Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, M. Kogălniceanu 1, RO-400084, Cluj Napoca, Romania.
Abstract:
Density functional theory calculations on the Co(2)(NO)(4)(SR)(2) compounds (R = CH(3), CF(3) and C(4)H(9)) predict butterfly and open isomeric structures with and without a direct Co-Co bond. The open Co(2)(NO)(4)(SR)(2) structures are favored over the butterfly isomers, in terms of relative energy. Furthermore the open structures are predicted to have approximately twice as large HOMO-LUMO gaps than the butterfly Co(2)(NO)(4)(SR)(2) isomers. For the related Co(2)(CO)(6)(SR)(2) species, competing open and butterfly structures with similar HOMO-LUMO gaps were predicted. This could explain why the Co(2)(NO)(4)(μ-SR)(2) compounds have already been synthesized and why no genuine Co(2)(CO)(6)(SR)(2) derivatives have yet been reported.
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